Anaplastic Thyroid Cancer

DESCRIPTION
* Anaplastic thyroid carcinoma is the least common type of Thyroid Cancer of the ones that begin in the gland itself. This is a very aggressive cancer, and often spreads quickly to surrounding tissues, as well as to distant sites. It is often seen in those over age 60, and the only risk factor may be previous surgery for cancer of the thyroid, in which only part of the gland was removed (i.e., partial thyroidectomy). This arises out a multinodular goiter -- usually, a quickly enlarging mass that compresses the surrounding tissues.
* Anaplastic thyroid carcinoma does not pick up iodine, making scanning with radioiodine of little use. Treatment involves surgical removal of the (entire) thyroid gland. As with scanning, because the cancer does not take up iodine, radioactive destruction of the cancer is not an option either.


SYMPTOMS
* Most people with Thyroid Cancer usually have painless swelling of the thyroid gland.
* The thyroid gland may be swollen all over, but most often only one area of the gland is affected. Often, there is a nodule (or lump) present, which is firm, painless, and does not move freely.
* Most Thyroid Cancers do not produce any thyroid hormone. Therefore, most people with Thyroid Cancer do not have symptoms of hyperthyroidism.
* Lymph nodes in the front part of the neck may be enlarged, but are usually not tender to touch.
* Growing very rapidly, this type of cancer can put pressure on some of the other structures in the neck and lead to trouble swallowing, difficulty breathing, or hoarse voice. It depends on its size, rate of growth, and location.

CAUSE
* It is not known what causes Thyroid Cancer.
* Anaplastic Thyroid Cancer spreads very early to the surrounding tissues, as well as to distant ones.

HOW THE DIAGNOSIS IS MADE
* The history, symptoms, and examination can help point the doctor in the right direction.
* However, the most effective method of diagnosis involves removing a piece of the thyroid and examining it under the microscope to see if cancer is present. This is usually done via a process known as FNA (fine needle aspiration), in which a needle is used to remove a sample of the lump.
* As stated above, in most cases of Thyroid Cancer, the tumor does not produce any thyroid hormone. Therefore, most people with Thyroid Cancer have normal thyroid tests.
* An Ultrasound of the neck is also helpful in determining the size of the cancer and to see if it has spread to other areas within the neck.
* Radioiodine scanning is not helpful (for reasons given above).
* Chest X-Ray, CT scan, MRI, or PET scan can also be helpful in detecting any metastatic disease.
* Laryngoscopy may be done if paralysis of vocal cords is suspected.

TREATMENT
* Treatment for almost all Thyroid Cancers begins with surgical removal of the thyroid -- usually the entire gland. In a few cases, only part is removed. The best surgical option should be discussed with your doctors.
* Surgery, if done by a skilled physician, is usually safe. There are potential complications and you should discuss these with your surgeon.
* However, one of the most common complications is accidental removal of the parathyroid gland because it is located very close to the thyroid. If this happens, it is generally not life threatening if detected early.
* Immediately after surgical removal of the thyroid gland, thyroid hormone replacement will be initiated, and will continue for the rest of the patient's life.
* Radioiodine scans and treatment with radioactive iodine are not options for those with anaplastic Thyroid Cancer because these cancers do not take up iodine.
* If Thyroid Cancer has spread to the bone, then radiation therapy may be needed.
* If the cancer has spread to the brain, then gamma knife radiation (a special type of radiation treatment) will be needed.
* After one has been treated for this condition, he will need to be followed very closely with periodic physicals, neck exams, and chest X-Rays. Monitoring for the correct amount of thyroid hormone replacement is requisite.
* The long-term outlook (or prognosis) is guarded for this type of cancer. The one-year survival is about 10% and the 5-year survival is only about 5%.

SIMILAR CONDITIONS
* Lymphocytic Thyroiditis
* Multinodular goiter
* Colloid nodules
* Benign follicular adenoma
* Metastatic Cancer

MISCELLANEOUS
* Special Information

1. Iodine is used by the thyroid gland to make thyroid hormone. Doctors can use this fact to their advantage by ordering a nuclear medicine scan using radioiodine when a problem with the thyroid is suspected. The patient is given radioiodine and if the gland is active, it will take up the radioiodine and use it to make thyroid hormone. A scan is performed to see what areas of the body are taking up the radioiodine. Radioactive iodine (131I) can then be used to destroy the cancer. Therefore, whether or not the cancer takes up iodine is very important in both the diagnosis and treatment of thyroid diseases.
2. Radioactive iodine is generally safe. However, depending on the dose and individual response to the medicine, it can cause side effects, including stomach inflammation, temporary low sperm count, low blood count, and, very rarely, leukemia.
3. To summarize -- if a lump is detected in the thyroid gland, first determine whether or not it is cancer. If cancer is present, then blood tests and X-Rays will be needed, followed by surgery to remove the cancer. In certain types of Thyroid Cancers, an iodine scan is administered to determine if the cancer has spread -- and radioactive iodine is used to destroy any Metastatic Cancer. (Anaplastic Thyroid Cancer, however, does not take up iodine, making this approach inapplicable in such cases). After surgery, in addition to receiving thyroid hormone replacement, survivors of this virulent cancer will have to be closely followed to make sure that the cancer does not come back.